Many young men in North America and Europe (but not in Asia) tend to think they need more muscle to be attractive. One study presented 196 young American men with 100 images of men with various levels...

Many young men in North America and Europe (but not in Asia) tend to think they need more muscle to be attractive. One study presented 196 young American men with 100 images of men with various levels of muscle. Researchers measure level of muscle in kilograms per square meter (kg/m²) of fat-free body mass. Typical young men have about 20 kg/m². Each subject chose two images, one that represented his own level of body muscle and one that he thought represented “what women prefer.” The mean gap between self image and “what women prefer” was 2.35 kg/m².

Suppose that the muscle gap in the population of all young men has a normal distribution with standard deviation 2.5 kg/m².

a) State the value that will be used to estimate the unknown population mean.

b)What is the critical z value for a 95 percent confidence interval for the mean amount of muscle young men think they should add to be attractive to women. (Enter answer to 2 decimal places)

c)Calculate the margin of error for a 95 percent confidence interval for the mean amount of muscle young men think they should add to be attractive to women. (Enter answer to 2 decimal places)

d)Using your answer from part c, what is the 95 percent confidence interval for the mean amount of muscle young men think they should add to be attractive to women. (Enter answer to 1 decimal place)